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Accession Number ADA565193
Title Wavelet Spectral Finite Elements for Wave Propagation in Composite Plates.
Publication Date Feb 2012
Media Count 17p
Personal Author R. Jha
Abstract The principal goal of this research is to advance the technology of structural health management (SHM) for composite structures. Wave propagation based methods have shown promise for SHM of composite structures. The spectral finite elements (SFE) method is highly suitable for wave propagation analysis due to its frequency domain approach which yields models that are many orders smaller than conventional FEM. Wavelet spectral finite element (WSFE) method overcomes the wrap around problem to accurately model 2-D plate structures of finite dimensions. The specific accomplishments of the research are: developed WSFE model for damaged composite plate with transverse crack; validated WSFE modeling of Lamb wave propagation in healthy composite plates through experimental measurements; implemented baseline-free Damage Force Indicator method for delamination detection using dynamic stiffness matrix from WSFE model of healthy plate; developed Modified Time Reversal method for Lamb wave based baseline-free damage diagnostics; and investigated effect of tone burst center frequency on instantaneous phase based delamination detection.
Keywords Composite structures
Damage detection
Lamb waves
Shm(Structural health management)
Structural health monitoring
Two dimensional
Wave propagation
Wsfe(Wavelet spectral finite element)

Source Agency Non Paid ADAS
NTIS Subject Category 71F - Composite Materials
63F - Optical Detection
46A - Acoustics
46E - Structural Mechanics
Corporate Author Clarkson Univ., Potsdam, NY. Dept. of Mechanical and Aeronautical Engineering.
Document Type Technical report
Title Note Final rept. 1 Apr 2009-30 Nov 2011.
NTIS Issue Number 1304
Contract Number FA9550-09-1-0275

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